DESCRIPTION: It is estimated that 3 million Americans have glaucoma,and 67 million peopleworldwidewill have glaucomaby2005. At least half do not know they have it because glaucoma usually has no symptoms in the early stages. Current research is aimed at developing methods of early diagnosis to detect the disease in the early stages, when treatment is most effective in minimizing irreversible vision loss. The identification of early pathologic changes at the Optic Nerve Head (ONH) is crucial to the diagnosis of glaucoma. The current gold standard for measuring these changes is through clinical stereoscopic observation of the ONH. From the American Academy of Ophthalmology (AAO) 2000, "Previous studies have found that the diagnostic precision of qualitative evaluation of stereoscopic ONHphotographs by experienced clinical observers is superior to any other currently available method of optic disc assessment" (Identifying Early Glaucomatous Changes, Wollstein, Health, 2000 AAOO). The major drawback to the stereoscopic evaluation is the subjectivity that creates inter- and intra-reader observer variability. A new method for evaluating the stereoscopic photographs is needed for consistent analysis of the changes on the ONH. This can be brought about by the use of quantitative analysis of the ONH changes. The Phase I project demonstrated a technique for calculating 3-dimensional topology of the ONH based on a pair of stereoscopic images. High correlations (> 0.9) between the manually annotated cup and disc and the automatically generated iso-disparity contours was documented. The principal aim of Phase II is to validate the technique by performing correlations with multiple readers and with existing clinical instruments such as the Heidelberg Retina Tomographer (HRT), and GDx Nerve Fiber Analyzer. The disparity algorithm's accuracy will be evaluated based on a phantom in the form of a model retina which has been machined with precise optic disc-like features. Such phantoms are used in radiology to calibrate tomography equipment. A second aim of the Phase II is to develop an interface for the use of the algorithm and to be tested in a clinical environment to demonstrate the software as a commercial grade product. Data for testing and validation will consist of traditional stereo fundus photography, digital stimultaneous photography, GDx nerve fiber analyzer, HRT,Goldman and Humphrey visual fields, and Inter Occular Pressure. PERFORMANCE SITE(S) (organization, city, state) Kestrel Corporation, Albuquerque, New Mexico Texas Tech University, Lubbock, Texas University of Texas, Health Sciences Center, San Antonio, Texas KEY PERSONNEL: Name Soliz, Peter Davis, Herbert Mitra, Sunanda Nemeth, Sheila Nutter, Brian Raman, Balaji Schluter, Mark Sponsel, William Yang, Shuyu Zamora, Gilberto Disclosure Permission Statement. Applicable PHS 398 (Rev. 05/01) Organization Kestrel Corporation Private Practice Texas Tech University Kestrel Corporation Texas Tech University Kestrel Corporation University of New Mexico University of Texas HSC Texas Tech University Kestrel Corporation to SBIR/STTR Only. See Instructions. IE Yes Page 2 Role on Project Principal Investigator Statistical Consultant Advisor for Algorithm Dev. Ophthalmology Technician Image Processing Support Algorithm Developer & Validation Medical Advisor Glaucoma Specialist, M.D. Registration & Algorithm Dev. Senior Engineer DNo Form Page 2 Principal Investigator/Program Director (Last, first, middle): Soliz, Peter The name of the principal investigator/program director must be provided at the top of each printed page and each continuation page. RESEARCH GRANT